• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.1
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• pp.53-61
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• 2015

This paper reports the test results of the floating floor system used to reduce the floor noise of apartment buildings. Recently, many soft resilient materials placing between the reinforced concrete slab and finishing mortar are used. The resilient material should not only reduce the floor impact sound vibration from the floor but also support the load on the floor. Thus, even if soft resilient materials satisfy the maximum limitation of light-weight impact sound and heavy-weight impact sound, these materials may not support the load on the floor. The experimental program involved conducting sixteen sound insulation floating floor specimens. Three main parameters were considered in the experimental investigation: resilient materials, loading location, and layers of floor. Experimental results indicated that the stiffness of resilient material significantly influenced on the structural behavior of floating floor system. In addition, the deflection of the floating concrete floor loaded at the side or coner of the specimen was greater than that of the floor loaded at the center of the specimen. However, the aerated concrete did not effect on the cracking strength of floating floor system.

• KIEAE Journal
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• v.7 no.1
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• pp.95-100
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• 2007

In apartment houses, said to be similar to a typical housing form, every household share the walls and floors. Many problems inevitably accompany such as an arrangement, as noise and vibration are shared among households. When investigating the percentage of apartment resident's dissatisfaction with housing environments, discontent due to noise ranks the highest. Among many different kinds of noises, noise such as floor crashing sounds show the highest indication rate in the residents' comparison of discontent. Therefore, it is the practice of insulating against noises such as floor crashing sounds that improves the apartment house environments. The factors influencing the floor impact sound insulation include floor finishing materials, shock absorbing floors (slabs included), and ceiling structures. The ceilings of the apartment houses, currently built in Korea, are set up with lower parts of slabs and paper finishing, or with double floors for protecting against floor impact sounds in order to improve the sound insulating performance. The most common the method of ceiling structure construction consists of 'wood boarded frames +Gypsum boards + ceiling papers', which is called the wood boarded frame method. This study aimed to measures and evaluates floor impact sound insulation by which the ceiling space are widened according to suppression system is added in apartment house ceiling structure.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.756-759
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• 2003

It is increasing the interest on the comfortable dwelling environment and the efforts to solve the problem of the floor impact noise in apartment houses have been realized, as a result numerous products have been made. The purpose of this study is to investigate the sound insulation performances according to foaming rate of floor impact noise insulators and flooring coverings in Mock-up Test Room. The test results of impact insulation performance for each floor impact noise insulators is that double structure of insulator is excel than one in low-middle frequency band and as foaming rate go up, the sound insulation performance is improved.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.10 s.115
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• pp.1036-1043
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• 2006

Damping materials for reducing heavy-weight floor impact noise in reinforced concrete structures were tested in apartment buildings. The effect of damping materials and an impact isolator were compared with an on-site experiment conducted in a high-rise apartment building. The loss factor of damping material analyzed more than 2 times than rubber to $1.5{\sim}2.3$, could know that Damping layer has excellent attenuation performance in side of vibration reduction. The results showed that the resonance frequency increased but vibration acceleration level decreased when the damping materials were used. The heavy-weight impact sound levels of the structure decreased substantially at 63 Hz, whereas the sound levels of the structure with the impact isolator increased.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.23 no.3
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• pp.274-281
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• 2013

Field measurement method of heavy/soft impact sound pressure level which is regulated in JIS and ISO has been using in Korea, Japan and Canada. It is reported that heavy/soft impact sound pressure level was varied by the sound field condition of receiving room such as sound absorption power and room volume. In this study, it is checked that heavy/soft impact sound pressure level was affected by the receiving sound field condition. Rubber ball and bang machine sound pressure level was measured in the vertically connected reverberation chamber. In oder to check the effect of receiving sound field on heavy/soft impact sound pressure, sound absorption power was changed with polyester sound absorption blankets with air space and glass wool. The reverberation time at 1 kHz band was changed from 10 s to 0.2 s by sound absorption material. Rubber ball sound pressure level measured without sound absorption material was 58 dB in $L_{i,Fmax,AW}$, but the level was 46 dB with sound absorption treatment. From this result, it is confirmed that sound field correction method is needed in the heavy/soft impact sound pressure level measurement method using bang machine and rubber ball.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.1142-1146
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• 2007

In this studies, subjective evaluation of heavy-weight floor impact sound through classification was conducted. Heavyweight impact sounds generated by an impact ball were recorded through dummy heads in apartment buildings. The recordings were classified according to the frequency characteristics of the floor impact sounds which are influenced by the floor structure with different boundary conditions and composite materials. The characteristics of the floor impact noise were investigated by paired comparison tests and semantic differential tests. Sound sources for auditory experiment were selected based on the actual noise levels with perceptual level differences. The results showed that roughness and fluctuation strength as well as loudness of the heavy-weight impact noise had a major effect on annoyance.

• Journal of KSNVE
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• v.9 no.3
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• pp.477-484
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• 1999

This study aims to present proper thickness of resilient mount and pattern of chips for the improvement of impact sound isolation. To achieve this aim, field tests were performed to evaluate the performance of impact sound isolation of pilot samples using waste tire chips against light and heavy-weight impacter, which samples were installed over concrete slabs of an apartment housing. In this study, the experiments were performed by the impact sound level of floors in KS F 2810 "Method for field measurement of floor impact level". As results, a flooring structure using waste tire chips as a resilient mount, with no relation to chip's types, has enhanced performance by 1~2 degree in light impact sound isolation, while it has improvement in heavy impact sound isolation. And fiber-type chips have better performance than granule-type ones when they overlaid concrete slab with 15~20 mm of thickness. For the improvement of impact sound isolation, it is recommended that insulating materials should be applied at joints between floating floors and walls, or floating floors and a doorframes, and also waterproof papers should be used for the effective thickness of resilient mount.ent mount.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.79-82
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• 2005

This study aims to propose fundamental data for development of noise reduction system that is applied to classification for light-weight impact sound. For this reason, eight types of damping materials were constructed in new construction field. Comparison and analysis among the reduction materials were carried out on the acoustical characteristics through test. In the end, the suitability as a damping material was evaluated by the analysis.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.14 no.8
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• pp.661-667
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• 2004

The characteristics of noise and vibration by a heavy impact source was studied. The triggering method was used for increasing the reliability and stability to measure the level of sound pressure. sound intensity and vibration acceleration. A simple finite element model and a rigid body analysis method were suggested to calculate the natural frequencies of the multi-layer floor system. The results show that the resilient materials decrease the natural frequency of the reinforced concrete slab, make a resonance with dominant driving frequency in the low frequency region, and increase the vibration and noise level. A simple finite element model and rigid body models was suggested to calculate the natural frequencies of the floor systems.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.05a
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• pp.383-386
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• 2005

Low frequency heavy-weight impact noise is the most irritating noise in Korean high-rise reinforced concrete apartment buildings. This low frequency noise is generated by foot traffic due to the fact that Koreans do not wear shoes at home. The transmission of the noise is facilitated by a load bearing wall structural system without beams and columns which is used in these buildings. In order to control low frequency heavy-weight impact noise, floating floors using isolation materials such as glass-wool mat and poly-urethane mat are used. However, it was difficult to control low frequency heavy-weight impact sound using isolation material. In this study, reinforcement of concrete slab using beams and plate was conducted. Using the FEM analysis, the effect of concrete slab reinforcement using FRP(fiber-glass reinforced plastic) on the bang machine impact vibration acceleration level and sound were conducted at the standard floor impact sound test building. The $3{\sim}4dB$ floor impact vibration acceleration level and impact sound pressure level were reduced and the natural frequency of slabs were changed.